1. Field of Invention
The invention relates to a cooling device and, in particular, to a cooling air gathering plate for a projector lamp.
2. Related Art
The cooling means of a conventional projector lamp is to use an air sending device to blow cool air toward the lamp reflector, the lampwick and any high-temperature position in the lamp, thereby taking away the heat of the lamp. As shown in FIG. 1, the high-temperature positions on the projector lamp 500 are the lampwick 510, the welding point 520, and the end point 530. When cooling the projector lamp 500 using the conventional means, the cooling air has a direct impact on the lampwick 510 whereas the welding point 520 and the end point 530 are not within the reach of the cooling air if the lamp reflector is shallow. Therefore, the welding point 520 and the end point 530 are less likely to be cooled. If the lamp reflector is deeper, there is an air current at the bottom of the lamp reflector. The air that absorbs the heat is not easy to exchange with the cool air, resulting in a worse cooling effect on the lampwick 510. However, the welding point 520 and the end point 530 obtain better cooling. As described above, the cooling effects on the parts of the projector lamp are different, or at least each part is not cooled appropriately according to their temperatures. Thus, the performance and lifetime of the lamp are sacrificed. If one uses a high-power projector, one has to use a larger air sending device or one with a higher rotation speed in order to enhance the cooling correspondingly. However, the larger air sending device occupies a larger space whereas the high-speed air sending device usually come with unbearable noises.